Automatic scraper for use in deep wells



Jan. 8, 1963 R. E. WINDERS 3,072,194

AUTOMATIC SCRAPER FOR USE IN DEEP WELLS Filed Oct. 28, 1958 2Sheets-Sheet 1 "w IIIHHI s AVAV/AVAWA% Jan. 8, 1963 R. E. WINDERS3,072,194

AUTOMATIC SCRAPER FOR USE IN DEEP WELLS Filed Oct. 28, 1958 2Sheets-Sheet 2 /6/ 773/ w A50 M w I 54' M5 44/ 45 w 6/ w /5Z UnitedStates Patent Ofifice 3,072,194 Patented Jan. 8, 1963 Filed Oct. 23,1958, Ser. No. 770,186 7 Claims. (Cl. 166-170) This invention isconcerned with oil-well scraping systems, in general, and morespecifically deals with a power operated scraping system. This systemincludes the fea tures of having necessary equipment so that it canoperate automatically to run through a complete cycle and stop, ready torepeat the same cycle at predetermined time intervals thereafter.

In many if not most producing oil-wells, the flow of oil up the tubing(or casing if the Well is not tubed) soon leaves a solid deposit ofparaffin or other solid matter on the walls of the tubing. Therefore, inorder to avoid a build up that will harmfully impair the flow of oil, itis necessary to periodically scrape the well free of such deposit. Thisscraping operation is an arduous job if done manually, and even if powerequipment is employed there is a lot of time consumed in maintaining afield of producing wells adequately scraped.

Consequently, it is an object of this invention to provide an improvedscraper system that will act unattended to scrape a deep well, or thelike, at predetermined periods.

Briefly, the invention includes an automatic scraper operating systemfor use in deep wells. Such system comprises in combination a scraperfor operation in a deep well, and means for suspending said scraperWithin said well plus means for moving said scraper over a predetermineddistance therein. The combination also includes motor means forperiodically driving said suspending means in order to move said scraperover said predetermined distance, plus control means for said motormeans which comprises timing means for initiating a scraping cycle andmeans for measuring a distance of travel of said scraper. The controlmeans also includes means actuated by said measuring means forcontrolling energization of said motor means to cause a complete cycleof operation, including running in one direction until said scraper hasmoved over the predetermined distance and running in the other directionuntil the scraper has been returned to its starting position.

The foregoing and other objects and benefits of the invention will bemore fully understood in connection with the description below, which isin greater detail. This more detailed description is illustrated in thedrawings, in which:

FIG. 1 is a side elevation, somewhat schematic in nature, showing themechanical elements of the system;

FIG. 2 is a schematic diagram, showing the pneumatic system that isinvolved in the control of the motor drive for running the scraperoperation;

FIG. 3 is an enlarged, detail view looking from the other side andpartially in cross-section, showing elements of both the measuring unitand one of a pair of threeway-control valves that are employed in thepneumatic control system; and

FIG. 4 is a longitudinal cross-section view, also enlarged, showing thepilot valve with its piston actuating unit.

Referring to FIG. 1, there is illustrated an oil well 11 that has acasing 12 therein in addition to tubing (not shown) in some instances.Attached to the top of the top of the tubing, and/ or the casing 12.,there is a pipe or tubular housing 13 for containing a scraper (notshown) when it is at the top of a scraping cycle, i.e. above the tubingthat is being scraped.

The scraper employed in any given instance may be one having manydifferent designs or forms. Generally it consists of certaincombinations of knife blades which are weighted so that they will fallof their own accord through the tubing or casing to be scraped. Thedetails of the scraper form no part per se of this invention.

Clamped or otherwise attached to the upper end of the pipe 13, there isa support bracket 16 that carries a pulley wheel 17 that is pivotedthereon for free rotation. There is a wire line 18 that has the scraperattached to the free end thereof, and that passes over the pulley 17 tobe wound upon a reel 21. Reel 21 is rotated under power by a pneumaticmotor 22. Motor 22. may be connected for driving the reel 21 in anyconvenient manner, e.g. by means of a belt 23 and pulley 24 that iscarried on the end of the shaft of motor 22. The reel belt 23 isattached for providing a speed reduction of the reel in any convenientmanner, e.g. by means of a V-belt-receiving groove around the peripheryof one side of the reel 21 itself.

The motor 22 is carried on a bracket 28 of any convenient structure,that is attached to a standard 29 which in turn has a base 3% and angledsupports 31 for holding the standard 29 in an upright position.

Standard 29 has bracket structure 34 attached near the top thereof, forcarrying the reel 21 in addition to other elements of the system. One ofthe other elements is a timing unit 35 that is a conventional unithoused in a generally rectangular box.

Also carried by the structure 34, there is a measuring unit 36 that hasa freely rotating wheel 37 so positioned as to have the wire line 18remain in friction-a1 contact with the periphery thereof at all times.Preferably the structure of the wheel 37 is such that there is a groovearound the edge thereof for accommodating the wire line 18. The sides ofsuch groove act to hold. the wire line within the groove; but, this isaided by means of an idler Wheel 38 which is preferably also maintainedin frictional contact with the wire line 18. Sufiicient force is used inthe frictional contact between Wire line 13 and the edge of measuringwheel 37, so that there will be no relative slippage therebetween; andthe rotation of the wheel 37 will correspond at all times with theposition of the scraper on the end of the Wire line 18.

Referring to FIG. 2, there is shown a schematic diagram of the pneumaticcontrol system that is employed with the various elements that areillustrated in FIG. 1. This control system determines the operation ofthe motor 22 in accordance with the positions of, i.e. the distancetravelled by, the scraper as determined by the measuring unit 36.

Operation of the motor 22 takes place in a cyclic manner automatically,with the initiation of each cycle determined by the timing unit 35.There is a valve 42 incorporated in the timing unit 35, and connectedinto a pneumatic circuit 43 that acts as the control circuit fordetermining the operation of the motor 22. In order to do this, thepneumatic circuit 43 has a branch that is connected to a piston 44 thatactuates a control valve 45, the details of which are illustrated inFIG. 4.

Control valve 45 acts to determine the direction of rotation of themotor 22, as well as to stop the operation of the motor when the valveis in its neutral position. Thus, there is a supply line 49 forintroducing pneumatic fluidunder pressure. Line 49 is connected to apressure regulator 50 which regulates the supply pressure to the motor22, so as to maintain it at a desired level. Then a pipe 51 carries thepneumatic fluid from the regulator 50 to an oil lubricator 52, fromwhich the pneumatic fluid is carried via a pipe 53 to a pressure inletport 57 (FIG. 4) of the control valve 45. Then the fluid flows eitherover a pipe 58 or another pipe 59 to the motor 22, depending upon theposition of the elements of control valve 45. The fluid exhausting fromthe motor 22, returns over the other of the pipes 58 or 59 and isdirected to an exhaust pipe 60 via a port 61 (see FIG. 4). Of coursepneumatic fiuid does not flow through either of the pipes 58 or 59 whenthe control valve 45 is in its neutral position.

As indicated above, the position of the control valve 45 is determinedby the piston 44. Piston 44 is in turn positioned pneumatically bypneumatic control circuit 43, that may be traced from the two sides ofthe piston 44 as follows. Commencing with the supply end of the circuitthere is a pipe 66 that is connected to a pressure regulator 67. Frompressure regulator 67 there is a pipe 68 that leads to parallelconnections made by pipes 69 and 70. Pipe 69 leads to one port of apressure actuated three way valve 74, while the pipe 70 leads to oneside of the timer actuated valve 42.

There may be a pressure gage 73 that indicates the line pressure of thepneumatic fluid being delivered to the control circuit 43.

Another port of the pressure actuated valve 74 is connected via a pipe75 to an inlet port of a special three way valve 76, that is actuated bythe measuring unit 36 in a manner that will be more fully disclosed inconnection with the detailed showing of FIG. 3. As will appear, thisthree way valve 76 is actually a specially constructed valve that hastwo separate valves connected mechanically together to provide thedesired valving action. The mechanical connection for these separatevalves is indicated by a dashed line 77 in FIG. 2. The structure of thisspecial valve 76 forms no part, per se, of this invention.

Connected to another port of the special three way valve 76, there is apipe 79 that connects in parallel to another pipe 80 as well as to apipe 81. The pipe 80 leads to the pressure actuator portion of anotherpressure actuated three way valve 84, while the pipe 81 leads to oneside of the piston 44, within a containing cylinder 85, therefor.

The space within the cylinder 85 on the other side of the piston 44 isconnected via a pipe 86, in parallel to a pipe 87 and a pipe 88. Pipe 88leads to an outlet port of another special three way valve 92, whilepipe 87 leads to the pressure actuator portion of the three way valve74. It will be noted that the mechanical connection between the twoseparate valves of special three way valve 92, is indicated by a dashedline 91.

The inlet port of valve '92 is connected via a pipe 93 to an outlet portof the three way valve 84. The inlet port of valve 84 is connected via apipe 94 to the other side of the time control valve 42. The operation ofthis pneumatic control circuit 43, will be described below following adescription of the details of the construction and operation of specialthree way valves 76 and 92, in additidn to those of the control valveand its actuating piston 44.

Referring to FIG. 3, there are shown some of the details of thestructure of the measuring unit 36, as well as the elements of one ofthe special three way valves 76 and 92, each of which is substantiallythe same as the other.

The measuring unit 36 is mechanically connected to both of the valves 76and 92, in order to actuate these valves at predetermined positions ofthe scraper that is connected to the end of the wire line 18. Movementof the wire line 18, as the scraper descends or is raised upward in thewell 11, causes the wheel 37 to rotate in one direction or the otherdepending upon which Way the scraper is travelling. Wheel 37 is fastenedsecurely to a worm 98 which is rotated with the wheel. Worm 98 mesheswith a worm gear 99 that is fastened to a shaft 191} and causes rotationthereof with the gear 99. Shaft 1% is connected into further reductiongearing situated in a housing 101 wihich encloses this reduction gearing(not shown). The whole reduction gear train terminates 4 at a shaft1192, situated with the actuating structure of the special three wayvalves 76 and 92 (FIG. 2).

Again referring to FIG. 3, and particularly to the details of one of thespecial valves 76 or 92 (the other being located behind, as viewed inFIG. 3); it is pointed out that there is securely attached to the shaft102, a pointed cam 103 that acts to position a cam follower arm 104,which in turn has a roller 1115 attached thereto by a stud 106.

Arm 10-4 has a longitudinally shiftable pivot structure (not shown) sothat as the cam 1153 moves clockwise (when viewed as shown in FIG. 3)the arm 164 will be urged, by means of the following roller 105, toshift its position longitudinally and slide upward while maintainingcontact with a stop pin 11%. Then as the roller 165 passes over the tipof the point on cam 1153, the arm 1114 will pivot and shift overcounterclockwise as roller 105 rolls down the other side of the pointedcam surface of cam 1113.

The above described action provides a snap acting shift of the camfollower arm 104, from the illustrated position to its other positionwhen it has rotated counterclockwise a small amount and has come to restin contact with another stop pin 111. It is pointed out that as thefollower arm 104 shifts from the position illustrated to the otherposition (resting against stop pin 111) it makes a longitudinal slidingmotion which allows the lower ex tremity of the arm 164 (which has apointed tip 112) to move longitudinally upward and then swing over tothe other side of a pin 113. Thus pin 113 acts to hold the arm 104 inone or the other of its two extreme positions, in a positive manner.

Pivotally connected to the follower arm 104, there is a push rod 116that rests in a cup shaped socket 117 in the end of a head member 118 ofa bleeder valve 119. The bleeder valve 119 includes a port 120 that isopened or closed by means of a seal ring 121 that surrounds a valve stem122 and rests against the under edge of the head element 118.

It is pointed out that when the cam follower arm 194 is in its otherposition from that illustrated, the push rod 116 will be shifted to theleft (as viewed in FIG. 3) so as to push the valve stem 122 over to theleft also, and close the valve by pressing the seal ring 121 against thesurface around the opening of port 120. Of course, in the positionillustrated, the valve of bleeder valve 119 is open allowing freepassage of fluid therethrough. The bleeder valve 119 thus acts to ventthe passages connected to the port 120 when it is open, but closes thispassage to prevent such venting when it is closed.

The port 1211 connects directly to a drilled passage 127 that is closedoff at the open end thereof by a gasket 128. However, there is an outletpassage 129 that connects with the passage 127.

On the end of the valve stem 122, there is a reduced diameter extension132 which extends through a passage 133. Passage 133 connects the insideends of the passage 127 and the port 121), with a drilled and partiallytapped hole 134 that contains a spring biased ball valve 135 insertedtherein. This hole 134 is connected via a groove and passage asillustrated, into communication with the inside end of another drilledpassage 136. Passage 136 is likewise closed at the other end thereof bythe gasket 128. However, connected into the side of the passage 136,there is an inlet passage 137 for pneumatic fluid that is under controlof the valve.

It will be noted that the ball valve 135 includes a bias spring 140, acall 141, and a valve seat 142. Also it will be noted that the extension132, of valve stem 122, rests against the ball 141. Thus, when the ballvalve 135 is closed (i.e. when it is in the position illustrated in FIG.3) the bleeder valve 119 is open. Also, vice versa, when the bleedervalve 119 is closed, the ball valve 135 will be opened, by reason of themovement of the valve stem 122 and the reduced diameter extension 132which will act to lift the ball 141 off its seat 142, and thus open theball valve 135. In this manner, the ball valve 135 and the bleeder valve1119 together go to make up a three way valve that acts in conjunctionwith the inlet and outlet passages 137 and 129 respectively, so as toeither close the passage 137 while venting the passage 129 to theatmosphere (at the open bleeder valve 119); or to directly connect thepassage 137 to the passage 129 without any ventmg.

As indicated above, there is an additional special three way valve,which includes all of the elements described above, e.g. a ball valveand a bleeder valve. These elements are substantially identical with theball valve 135 and the bleeder valve 119 described; and therefore in theschematic indication of these valves in the control system (FIG. 2), thereference numbers for the ball valves and bleeder valves that are usedare 135, 119 and 135', 119 respectively. This additional valve structureis located behind the elements illustrated in FIG. 3, and is set up foractuation at a desired position of the scraper that is attached to thewire line 18, in accordance with the desired action of the system thatwill be more fully described below.

Referring to FIG. 4, it is pointed out that there are illustrated thedetails of the control valve 45, which valve determines the operation ofthe pneumatic motor 22. This control valve 45 is a commercial item andneed not be described in great detail; but for complete understanding ofthe operation thereof, reference to FIG. 4 may be had wherein it will beobserved that there is a central shaft 146 that has attached at one endthereof the piston 44 which is carried by the cylinder 85. The cylinder85 has passages 148 and 149 for introducing pneumatic fluid on eitherside of the piston 44, within the cylinder 85. It will be noted that thepipe 81 (FIG. 2) will be connected to the passage 14?, while the pipe 86(FIG. 2) will be connected to the passage 148.

At the other end of the shaft 146 from piston 44, there is a springcentering-structure for longitudinally biasing the shaft 146 into aneutral or central position, i.e. that illustrated in FIG. 4 herein.This centering mechanism includes a spring 152 that is under compressionfrom a washer 153 at one end thereof, and a flanged grommet 154 at theother end. Grommet 154 is held in place around the end of the shaft 146,by means of a washer 155 and a hexagonal out 156 that is received by athreaded tip 157 on the shaft 146. The washer 153 rests against ashoulder 16%} that is formed on the shaft 146 where its diameter issharply reduced.

In this manner, whenever the shaft 146 is moved longitudinally to theright (as viewed in FIG. 4) the washer 153 will be moved also to theright and will cause the spring 152 to be additionally compressed.Similarly, whenever the shaft 146 is moved longitudinally to the left,the flanged grommet 154 will be moved to the left therewith by reason ofits attachment to the shaft, and the spring 152 will again becompressed. Thus, the shaft 146 is under a spring bias tending to returnit to the neutral position from either direction that it may be movedtherefrom.

The valve passages involved in the control valve 45 are clearlyillustrated, and will be only briefly referred to as follows. Port 57has a common passage 161 that con- ,nects the port 57 to the two annularspaces between the pairs of seals (illustrated) at either end of thepassage 161. The port 61, on the other hand is directly connected to asingle annular space that surrounds the shaft 146 between the centermostpair of seals. It will be noted that the shaft 146 has two reduceddiameter portions 162 and 163 which lie adjacent to annular spaces 164and 165 respectively. These spaces 164 and 165 surround the shaft 146,and lie between pairs of seals as illustrated. Connected to each or" theannular spaces 164 and 165, there is a separate passage 166 and 167respectively which in turn is connected to one of a pair of ports 168and 169.

6 The pipes 59 and 58 (FIG. 2) that lead to the pneumatic motor 22, areconnected to the ports 16% and 169.

Now it will be clear that when the control valve 45 is in the neutralposition, as illustrated in FIG. 4, no flow of fluid is permitted fromany one of the ports to another. However, when the piston 44 is shiftedto the right (as viewed in FIG. 4) the shaft 146 will likewise belongitudinally moved to the right, and the reduced diameter portions 162and 163 will move over so as to provide a passageway for connection fromthe passage 161 to the passage 167, past a seal 172 that will now lieopposite the reduced diameter portion 163. At the same time the otherreduced diameter portion 162 similarly will lie across a seal 173, sothat the port 61 and its connected annular space around the shaft 146,in turn will be connected to the space 166. Then, of course, the reversesituation will hold true when the piston 44 is shifted to the left, andconsequently at such time the port 61 will be connected to the space 167while the port S7 (via passage 161) will be connected to the space 166and port 168.

Operation Referring now to FIG. 2, the operation of the system will bedescribed in greater detail. The operation may be thus described byfollowing the action of the apparatus through a complete cycle, asinitiated by the timing unit 35.

When the timing unit 35 reaches a set predetermined time the valve 42thereof will be opened and pneumatic fluid under pressure (as regulatedby regulator 67) will be allowed to flow through pipe 94 and continuevia three way valve 84 which is at this time open for through passagesince the diaphragm actuator thereof is not under pressure. It will beobserved that there may be a gage 176 on the down stream side of thevalve 42. to show the pressure on the control circuit side of thisvalve.

Pneumatic pressure is thus introduced into the pipe h?) and thence tothe ball valve of the special three way valve 92, that is actuated bythe measuring unit 36 as described above. At this time, the cycle willbe just beginning and the scraper will be at the top of the well 11 sothat wire line 18 will be fully reeled up onto the reel 21. It will beremembered that the special three way valve 92 has structure for theball valve 135 and bleeder valve 119' that is substantially identicalwith the corresponding structures that were described in detail above.

At this stage in the operation the special three way control valve 92 isset in its cocked position so that there is a passage open between thepipe 93 and the pipe 88 leading from the other opening or passageway ofthe three way valve structure, i.e. ball valve 135' is open. At the sametime the bleeder valve 119 is closed to prevent bleeding of pneumaticfluid at the special valve 92 at this time. Consequently, pneumaticpressure will be introduced to the pipe 88 and thence pipe 87 as well aspipe 86. This will cause the piston 44 to be moved to the right, so asto shift control valve 45 over and cause the pneumatic motor 22 to beenergized to run in the proper direction to feed out the wire line 18,and cause the scraper to descend in the well 11. Also, pneumaticpressure in pipe 87 will cause the three way valve 74 to be actuated, sothat the pipe 69 is shut off at the valve 74 while the pipe 75 is ventedto atmosphere at the valve 74.

Before the foregoing first step of the operation in a given cycle takesplace, the left hand special three way valve '76 is in its so-calledtripped position (like that illustrated in FIG. 3) so that the ballvalve 135 is closed and the pipe 75 is not free to vent to atmosphere atthe special three way valve 76.

Now, as the wire line 18 is payed out and the scraper descends in thewell 11, the adjustments are such that after about 500 feet of traveldown the well, the special three way valve 76 is shifted to its cockedposition (ball valve 135 open and bleeder valve 119 closed) and thescraper continues to descend.

It is to be noted that at the first step, i.e. when piston 44 wasshifted by introduction of the pneumatic pressure on the left sidethereof (via pipe 86) the pneumatic fluid present on the right hand sideof the piston was allowed to exhaust via pipe 81 and pipe 79, to thespecial three way valve 76. This exhaust path was open because thebleeder valve 119 of valve 76, was at this time open while the ballvalve 135 thereof was closed.

Now, when the scraper reaches a predetermined depth in the hole as setby the adjustment of the cam 103 (not shown) on the shaft ltlZ (otherend from that in view in PEG. 3) the special three way valve 92 istripped; and thus the bleeder valve 119 thereof opens, while the ballvalve 135 thereof is closed. This means that the pressure on the lefthand end of piston 44 is released and the piston returns to its neutralposition stopping the motor 22. However, because the special three wayvalve 76 was previously cocked (when the scraper had descended aboutfive hundred feet), the pneumatic fluid pressure is now introduced tothe right hand side of piston 44, via the pipes 75, 79 and 81. This lastnamed pneumatic circuit is completed with the venting of pressure on theleft hand side of the piston 44; because the pressure in pipe 87 is alsorelieved with that on the left side of piston 44 (pipe 86), and thepressure actuated valve 74 then returns to its no pressure position, sothat the pneumatic fluid circuit from pipe 69 to pipe 75 is connected.

Thus the motor 22 will immediately start up again in the oppositedirection, and begin raising the scraper by reeling in the wire line 18.

After the scraper has been raised upward from its lowest position forabout five hundred feet, the other special three way valve 92 will againbe cocked so that its ball valve 135 will be opened while its bleedervalve 119 is closed. This accomplishes the setting of this valve in theproper position for the commencement of the next cycle. During the fivehundred feet before the valve 92 is cocked, the escape of pneumaticfluid at the vent of the bleeder valve 119' is prevented because thethree way valve 84 stands pressure actuated by reason of the pneumaticpressure supplied by the pipe 8%, which is in parallel with thepneumatic pipe 81 that is supplying pressure to move the piston 44 tothe left.

In regard to the valves 74 and 84, it is pointed out that the three wayvalve 84 acts to cut off the passage connected to pipe 94 while ventingthe passage connected to pipe 93, when it is actuated by pressure.Similarly, the three way valve 74 acts to cut off the passage connectedto pipe 69 while venting the passage connected to pipe 75, when thevalve is actuated by pressure (in p1pe 87),

At this point, it may be noted that the timlng un1t 35 is set so thatthe valve 4 2 controlled thereby remains open during the first half ofthe cycle and continuing on until sometime after the scraper is beingraised from 1ts lowermost position. Usually this time will be set to beabout at the point when the scraper is half way up out of the hole. Thisthen sets up conditions so that the operation will stop at the top ofthe cycle and await the opening of valve 42 again before commencinganother cycle.

The completion of a cycle comes when the wire line 18 has been reeled upon the reel 21 until the scraper has been raised to the top of itstravel. This condition is act by adjustment of the connection frommeasuring unit 36 to the cam actuated elements of special three wayvalve 76. This adjustment is made by the position of the cam 103 on theshaft 102. These are adjusted so that the .valve 76 will be tripped whenthis top position is reached.

Such tripping of the valve will, of course, open the bleeder valve 119while closing the ball valve 135 and these actions will cause the piston44 to return to neutral since the pressure on the right hand side of thepiston will be relieved at the bleeder valve 119. Also, the pneumaticfluid pressure will be maintained within the pipe 75 by the closing ofthe ball valve 135.

The adjustments mentioned above for the cams of special three way valves76 and 92, include Vernier adjustment elements 177 (FIG. 3) for accuratesetting of the tripping positions of these valves at the desired travelpositions of the scraper.

It will be observed that by means of the apparatus in accordance withthis invention a scraping cycle may be provided which takes placeautomatically, unattended, and may be set to repeat at predeterminedintervals as desired. This action is accomplished by providing theconnection, or mechanical tie, with the position of the scraper (asdetermined by its wire line) to act upon the pneumatic controlarrangement for energizing the motor that unreels and reels the wireline which supports the scraper.

It is pointed out that there may be a level wind arrangement (not shown)incorporated into the reel drive, if desired, in order to avoid anybinding or snarling of the wire line, particularly in a deep hole.

While a particular embodiment of the invention has been described inconsiderable detail in accordance with the applicable statutes, this isnot to be taken as in any way limiting the invention but merely as beingdescriptive thereof.

What is claimed as the invention is:

1. An automatic scraper operating system for use in deep wellscomprising in combination, a scraper for operation in a deep well, awire line for suspending said scraper within said well, a reel forcontaining said wire line to position said scraper over the length ofthe well, a pneumatic motor connected to drive said reel for moving thescraper up and down the well, and a control system for said motorcomprising a piston actuated valve for reversibly controlling the supplyof pneumatic fluid to the motor having a piston and cylinder means foractuation thereof, a measuring wheel unit in contact with said wire lineto determine the position of the scraper in the well, a timing unithaving a valve actuated by said timing unit, a first pair of three wayvalves connected to and for actuation by said measuring wheel unit, asecond pair of three way valves each having pressure controlledactuators, and a pneumatic circuit for controlling the actuation of saidpiston including a connection for receiving pneumatic fluid underpressure, a parallel circuit connection from said receiving connectionto one side of said timing unit valve and to one of said second pair ofthree way valves, a circuit connection from said one of the second pairof three way valves to one of said first pair of three way valves, aparallel circuit connection from said one of the first pair of three wayvalves to the actuator of the other of said second pair of three Wayvalves and to one side of said piston, a circuit connection from theother side of said timing unit valve to the other of said second pair ofthree way valves, a circuit connection from said other of said secondpair of three way valves to the other of said first pair of three wayvalves, a parallel circuit connection from said other of the first pairof three way valves to the actuator of the said one of said second pairof three way valves and to the other side of said piston, wherebyactuation of said timing unit valve will initiate a cycle of scraperoperation to cause said motor to run in a predetermined direction untilone of said first pair of three way valves is actuated when the motorwill be reversed and run in the opposite direction until the other ofsaid first pair of three way valves is actuated when the motor will bestopped because of the closing of said timing unit valve in themeantime.

2. An automatic scraper operating system for use in deep wellscomprising in combination, a scraper for operation in a deep well, aline for suspending said scraper within said well and for moving saidscraper over a predetermined extended vertical distance therein, a reel,said line wound thereon, reversible motor means adapted to travelthrough a cycle for driving said reel to move said scraper over saidpredetermined distance and return, and cyclic control means for saidmotor means comprising a timing unit having means for initiating saidcycle, means for measuring the distance of travel of said scraper, meansactuated by said measuring means for controlling energization of saidmotor means to cause a complete cycle of operation thereof includingrunning in one direction until said scraper has moved over thepredetermined distance and running in the other direction until thescraper has been returned to its starting postion.

3. An automatic scraper operating system for use in deep wellscomprising in combination, a scraper for operation in a deep well, aline for suspending said scraper within said well and for moving saidscraper over a predetermined extended vertical distance therein, a reel,said line wound thereon, reversible pneumatic motor means adapted totravel through a cycle for driving said reel to move said scraper oversaid predetermined distance and return, and cyclic control means forsaid motor means comprising a timing unit having means for initiatingsaid cycle, means for measuring the distance of travel of said scraper,means actuated by said measuring means for controlling energization ofsaid motor means to cause a complete cycle of operation thereofincluding running in one direction until said scraper has moved over thepredetermined distance and running in the other direction until thescraper has been returned to its starting position.

4. An automatic scraper operating system for use in deep wellscomprising in combination, a scraper for operation in a deep well, aline for suspending said scraper within said well and for moving saidscraper over a predetermined extended vertical distance therein, a reel,said line wound thereon, reversible pneumatic motor means adapted totravel through a cycle for periodically driving said reel to move saidscraper over said predetermined distance and return, and cyclic controlmeans for said motor means comprising a timing unit having means forinitiating said cycle, means for measuring the distance of travel ofsaid scraper, a pilot valve for controlling opertion of said motor, apneumatic system connected to said pilot valve including control valvemeans actuated by said measuring means for causing a complete cycle ofoperation thereof to take place after initiation by said timing means.

5. An automatic scraper operating system for use in deep wellscomprising in combination, a scraper for operation in a deep well, aline for suspending said scraper within said well and for moving saidscraper over a predetermined extended vertical distance therein, a reel,said line wound thereon, reversible pneumatic motor means adapted totravel through a cycle for periodically driving said reel to move saidscraper over said predetermined distance and return, and cyclic controlmeans for said motor means comprising a timing unit having means forinitiating said cycle, means for measuring the distance of travel ofsaid scraper, a pilot valve for controlling operation of said motor,pneumatic circuit means for controlling said pilot valve including apiston and cylinder means for actuating said pilot valve, a valvecontrolled by said initiating means, a pair of valves controlled by saidmeasuring means, pneumatic circuit connections for connecting saidpiston and cylinder means with said pair of valves and said initiatingvalve in order to cause a complete cycle of operation after initiationthereof by said timing unit.

6. An automatic scraper operating system for use in deep Wellscomprising in combination, a scraper for operation in a deep well, aline for suspending said scraper within said well and for moving saidscraper over a predetermined extended vertical distance therein, a reel,said line wound thereon, reversible pneumatic motor means adapted totravel through a cycle for driving said reel to move said scraper oversaid predetermined distance and return, and cyclic control means forsaid motor means comprising a timing unit having means for initiatingsaid cycle, means for measuring the distance of travel of said scraper,a pilot valve for controlling operation of said motor, pneumatic circuitmeans for controlling said pilot valve including a piston and cylindermeans for actuating said pilot valve, a valve controlled by saidinitiating means, a first pair of valves controlled by said measuringmeans, a second pair of valves controlled by the pressure applied tosaid piston, pneumatic circuit connections for connecting said pistonwith said first and] second pairs of valves and said initiating valveand including a circuit connection for receiving a supply of pneumaticpressure, all whereby a complete cycle of operation will take placeautomatically after initiation thereof by said timing unit.

7. An automatic scraper operating system for use in deep wellscomprising in combination, a scraper for operation in a deep well, aline for suspending said scraper within said well and for moving saidscraper over a predetermined extended vertical distance therein, a reel,said line wound thereon, reversible pneumatic motor means adapted totravel through a cycle for driving said reel to move said scraper oversaid predetermined distance and return, and cyclic control means forsaid motor means comprising a timing unit having means for initiatingsaid cycle, means for measuring the distance of travel of said scraper,a pilot valve for controlling operation of said motor, pneumatic circuitmeans for controlling said pilot valve including a piston and cylindermeans for actuating said pilot valve, a valve controlled by saidinitiating means, a first pair of valves controlled by said measuringmeans, a second pair of valves controlled by the pressure applied tosaid piston, a pneumatic circuit including a connection for receiving asupply of pneumatic pressure, a connection to one side of saidinitiating valve and to one of said second pair of valves, a connectionfrom the other side of said initiating valve to the other of said secondpair of valves, connections from each of said second pair of valves toone of said first pair of valves respectively, and other connectionsfrom said first pair of valves in parallel to one side of said pistonand to the control element of one of said second pair of valvesrespectively, said pneumatic circuit connections being so arranged thatsaid initiating valve actuation will supply pressure to one side of saidpiston and cause said motor means to drive said suspending means in apredetermined direction until one of said first pair of valves isactuated by said measuring means, and then supply pressure to the otherside of said piston while venting the first named side thereof until theother of said first named pair of valves is actuated by said measuringmeans to vent the other side of the piston and stop the scraping cycle.

References Cited in the file of this patent UNITED STATES PATENTS260,501 Roberts July 4, 1882 2,415,729 Dana Feb. 11, 1947 2,475,160Stamos July 5, 1949 2,678,696 Crake May 18, 1954

1. AN AUTOMATIC SCRAPER OPRATING SYSTEM FOR USE IN DEEP WELLS COMPRISINGIN COMBINATION, A SCRAPER FOR OPERATION IN A DEEP WELL, A WIRE LINE FORSUSPENDING SAID SCRAPER WITHIN SAID WELL, A REEL FOR CONTAINING SAIDWIRE LINE TO POSITION SAID SCRAPER OVER THE LENGTH OF THE WELL, APNEUMATIC MOTOR CONNECTED TO DRIVE SAID REEL FOR MOVING THE SCRAPER UPAND DOWN THE WELL, AND A CONTROL SYSTEM FOR SAID MOTOR COMPRISING APISTON ACTUATED VALVE FOR REVERSIBLY CONTROLLING THE SUPPLY OF PNEUMATICFLUID TO THE MOTOR HAVING A PISTON AND CYLINDER MEANS FOR ACTUATIONTHEREOF, A MEASURING WHEEL UNIT IN CONTACT WITH SAID WIRE LINE TODETERMINE THE POSITION OF THE SCRAPER IN THE WELL, A TIMING UNIT HAVINGA VALVE ACTUATED BY SAID TIMING UNIT, A FIRST PAIR OF THREE WAY VALVESCONNECTED TO AND FOR ACTUATION BY SAID MEASURING WHEEL UNIT, A SECONDPAIR OF THREE WAY VALVES EACH HAVING PRESSURE CONTROLLED ACTUATORS, ANDA PNEUMATIC CIRCUIT FOR CONTROLLING THE ACTUATION OF SAID PISTONINCLUDING A CONNECTION FOR RECEIVING PNEUMATIC FLUID UNDER PRESSURE, APARALLEL CIRCUIT CONNECTION FROM SAID RECEIVING CONNECTION TO ONE SIDEOF SAID TIMING UNIT VALVE AND TO ONE OF SAID SECOND PAIR OF THE THREEWAY VALVES, A CIRCUIT CONNECTION FROM SAID ONE OF THE SECOND PAIR OFTHREE WAY VALVES TO ONE OF SAID FIRST PAIR OF THREE WAY VALVES, APARALLEL CIRCUIT CONNECTION FROM SAID ONE OF THE FIRST PAIR OF THREE WAYVALVES TO THE ACTUATOR OF THE OTHER OF SAID SECOND PAIR OF THREE WAYVALVES AND TO ONE SIDE OF SAID PISTON, A CIRCUIT CONNECTION FROM THEOTHER SIDE OF SAID TIMING UNIT VALVE TO THE OTHER OF SAID SECOND PAIR OFTHREE WAY VALVES, A CIRCUIT CONNECTION FROM SAID OTHER OF SAID SECONDPAIR OF THREE WAY VALVES, A PARALLEL CIRCUIT CONNECTION FROM SAID OTHEROF THE FIRST PAIR OF THREE WAY VALVES TO THE ACTUATOR OF THE SAID ONE OFSAID SECOND PAIR OF THREE WAY VALVES AND TO THE OTHER SIDE OF SAIDPISTON, WHEREBY ACTUATION OF SAID TIMING UNIT VALVE WILL INITATE A CYCLEOF SCRAPER OPERATION TO CAUSE SAID MOTOR TO RUN IN A PREDETERMINEDDIRECTION UNTIL ONE OF SAID FIRST PAIR OF THREE WAY VALVES IS ACTUATEDWHEN THE MOTOR WILL BE REVERSED AND RUN IN THE OPPOSITE DIRECTION UNTILTHE OTHER OF SAID FIRST PAIR OF THREE WAY VALVES IS ACTUATED WHEN THEMOTOR WILL BE STOPPED BECAUSE OF THE CLOSING OF SAID TIMING UNIT VALVEIN THE MEANTIME.